Field of the Invention
The present invention relates to a technique for correcting image shake using a plurality of image shake correcting units.
Description of the Related Art
In recent years, along with a decrease in size of an imaging apparatus and an increase in magnification of an optical system, a shake of an imaging apparatus or the like becomes a large factor which reduces the quality of a shot image. In this regard, various image shake correction functions of correcting image shake of a captured image caused by a shake of an apparatus or the like are proposed. Japanese Patent No. 4518197 discloses a control method using a plurality of shake correcting units in combination as a shake correction function mounted in an imaging apparatus. An angular velocity sensor signal is separated into a low frequency band and a high frequency band so as to perform image shake correction of an imaging apparatus by means of the shake correcting units.
In the technique disclosed in Japanese Patent No. 4518197, correction in the low frequency band and correction in the high frequency band are fixedly assigned to two shake correcting units. However, in the case of an imaging apparatus including, for example, a zooming optical system, the correctable amounts of two shake correcting units may vary depending on the zooming magnification as shown in FIG. 5. The correctable amount of each shake correcting unit is determined by the light quantity balance, the MTF (Modulation Transfer Function) properties, and the like of an imaging optical system.
Shake applied to an imaging apparatus has properties such that the amplitude increases at lower frequency but decreases at higher frequency. Thus, it is contemplated that, for two shake correcting units, correction in the low frequency band is assigned to one of them having a large correctable amount and correction in the high frequency band is assigned to the other having a small correctable amount. When the relationship in magnitude between the correctable amounts of two shake correcting units varies with a change in zooming magnification as shown in FIG. 5, optimum shake correction control can be performed by changing the assignment of correction in the high frequency band and correction in the low frequency band to two shake correcting units.